The shutdown client is a simple command-line program that transmits a group name using UDP. And machine running the [[shutdown-service|Shutdown Service]] will receive the message and automatically turn off the machine.

The Shutdown service is an NT service that uses a UDP listener. If it receives a message on the configured port and the group name specific is in its configuration list file, then it will automatically shutdown the machine.

The configuration file is named UDPGroup.txt and just contains a list (one entry per line) of the names that it will respond to.